How Bionic Technology Can Restore Function To The Human Body

bionic hand being worn by human

Bionic technology has always had a primary focus on restoration – the replacement of lost or malfunctioning body parts to get the user back to their normal life as quickly as possible.

Second to that is enhancement, where the limits of the human body are temporarily exceeded by either increasing technical aptitude or opening a new function that would otherwise be unavailable/unusable naturally.

Image of bionic hand using bionic technology to enhance the ability to use the hand
Featured Image credit by This is Engineering via Flickr

But, in order to achieve the wonders of bionics when it primarily comes to body repair, there are a few fundamental medical principles and several technologies that need to be combined first. Depending on the specific end goal, there may be countless variations within these types of design considerations, which may be further supported by newer and more groundbreaking medical concepts.

Human body repair by restoring lost functions

As already previously discussed numerous times, the first priority in using bionics for human body repair is to bring back what was lost via artificial component replacement. More accurately speaking:

1. Accurate mechatronic replication of movement for limbs

If the bionic component is meant to replace a limb, using hardware that can match the movement of the lost body part closely is usually the most straightforward solution. The mechatronic equivalent of such movements is easy enough to replicate using current robotics technologies. However, the level of restored usability for the upper and lower limbs still varies greatly.

For legs and feet, today’s bionic technology is already at a level where it could easily match the gait, pacing, movement, and sometimes even reflexes of the original. There is the issue of cost, where the better ones are usually reserved only for those who can afford them. But the options do exist, and we can use them right now.

In fact, if we extend our definition beyond advanced bionics, and into simpler prosthetics, we can show that artificial components have long surpassed the movement capabilities of regular human legs.

The Flex-Foot Cheetah prosthetic by Ossur, for example, was even once considered temporarily an “unfair technical device” by the World Athletics (formerly IAAF), which banned its use by disabled athletes from 2007 to 2008.

For arms, hands, and fingers, articulation has greatly improved over the last two decades, with products such as i-Limb demonstrating modular finger adjustment capabilities similar to how normal hands adjust fingers.

The speed at which each movement is made, however, still requires significant improvement. There is just so much more information that needs to be processed with the upper limb, and not all of it can be translated effectively by simple residual muscle movement from the amputated part.

The current trend in designing commercial bionic arms is simply providing a pre-set number of different grip modes, which thankfully can be toggled between each other using the same myoelectric sensor systems.

It’s not as graceful as full modular movement, but it is more practical, caters to many purposes despite using simpler technologies, and is cost-effective, so that more people can benefit from at least partial limb use restoration.

2. Alternative physical processing for organs with usable relative efficiency

For other bionic components, such as bionic organs, the ideal objective is to find a different artificial mechanism that can mimic the original body part (hopefully with similar efficiency). Right now, though, the best that we can do is to restore a fraction of it in an effort to prevent the function from being lost altogether.

Bionic eyes, for example, can have a wide variety of designs depending on which part of the eye requires an artificial replacement. If retinal imaging is required, a composite electronic film can be used for very basic transduction of light, which would then be interpreted by the user as intensity levels. If light focus needs to be restored, a dynamically adjusting lens can be used, which can potentially eliminate the need to wear any other eye augmentations.

concept bionic eye

For more critical body parts, such as the heart and kidneys, it is an absolute requirement that a certain level of efficiency must be met, and that the mechanics of operation should be close enough to what the original organ does. As such, while a wearable artificial kidney is acceptable enough for basic, remedial use, something like a fully developed version of the bioartificial kidney would suit much better as a true bionic organ replacement.

Human body repair by reclaiming intuitive use

As described by the sub-header, repairing the human body via bionics also requires keeping the artificial component usable at a level and method similar to the lost biological part. For a more detailed explanation of the technologies mentioned here, please refer to our previous article on how do bionic limbs work:

Recreating a movement map that residual muscles already use – standard bionic limbs make use of sensors attached to strategic points of the amputated part, where the tiny movement of the remaining muscles in that area is used to “cue” the bionic limb on how to move.

There are currently three methods to achieve this. The first is by simply using the muscles and nerves already there (standard myoelectric). Second is by rewiring the nerves to other muscles makes the sensor layout even more refined (targeted muscle reinnervation). Third is by using the integrated bone-metal composite structure to add tactile feedback to limb movement (osseointegration).

Letting AI learn the user’s habits – once the user starts to get used to all of the features of the new bionic limb, one added option to optimize its use further is to have an AI predict the set of motions that the user intends to do. If implemented properly, fully articulate or modular movement may not even be a necessity for more advanced units, essentially becoming a new version of “muscle memory” for the user.

Human body repair focusing on keeping your body “normal”

Some of these are not strictly required for pure function, but rather for the social advantages that they provide for bionics technology users living in our modern era:

  • Living life closer to what it once was –  with a fully implemented bionics system, it is possible for users to live out their remaining lives not having to worry about losing their jobs or missing out on what they previously enjoyed. This is true, even if the bionic component does not exactly bring back the lost body part to 100% functionality.
  • Mimicking natural movement or function – At least for bionic limbs, if the artificial components are able to get close enough to natural body movement, living their new “cyborg” lives wouldn’t feel as awkward. Imagine being able to walk or run to and from your workplace as if no accident had ever occurred in the first place.
  • Making bionic components unnoticeable – for other users, adding cosmetic elements to bionic components is also another way of going back to society as a “normal” person. Sure, some people absolutely love the cool aspect of having robotic body parts. But some people might prefer to be a bit more discreet, preferring not to reveal that they even had artificial components in the first place.
  • Preventing further complications (muscle fatigue, infections, pressure on amputated part) – earlier bionic limbs had issues when it came to fitting the artificial components to the amputated body part. Today, most of these problems are technically fixed for modern bionic components. At the very least, there are a couple of extra product maintenance procedures to make them a complete non-issue.

More information, more body repair options but also more complexity

Other research groups and commercial entities are toying with several ideas to add more sensory information for the bionic components to process. After all, the natural hand, finger, or lung doesn’t just exchange information exclusively with the brain. The hands and fingers have to account for touch and grip, while the lung adapts to different levels of air breathability.

At the moment, though, these technologies are treated more as add-ons, as opposed to being an integral part of the system. Sure, having a sense of touch does help in reclaiming intuitive use and in keeping your body normal. But much like how modular movement is sacrificed for simpler grip modes, they have yet to be designed at a level that is elementary enough that we won’t even question why they are required.

That being said, having your bionic kidney activity monitored per unit quantity wirelessly does sound like the greatest dream of data optimizers (or the worst nightmare of privacy paranoids).